Well, any size dog can bite. I think it's just a matter of the situation at hand. Obviously I'm biased because I sleep with four pitbulls, but I think I'd try to baby a small dog too much if I had one.
My BFF has two tiny dogs and I try to carry them around with me as much as possible when I see them. I also buy them tiny jackets. One of them likes to lick up my nose.